A capacity and minimum guarantee-based service class-oriented scheduler for LTE networks

Quality-of-service (QoS) requirements have always posed a challenge from scheduling perspective and it becomes more complicated with the emergence of new standards and applications. Classical techniques like maximum throughput, proportional fair, and exponential rule have been used in common network scenarios but these techniques fail to address diverse service requirements for QoS provisioning in long-term evolution (LTE). These QoS requirements in LTE are implemented in the form of delay budgets, scheduling priorities, and packet loss rates. Scheduler design for LTE networks therefore requires handling service class attributes but preciously proposed scheduling methods ignored service class-based design and focused more on single network prospect. To address service class requirements in LTE, we propose a modified radio resource management-based scheduler with minimum guarantee in the downlink following network capacity and service class attributes defined in LTE standard. The scheduler takes advantage of best available channel conditions while maintaining data rates corresponding to minimum resources guaranteed for all major classes including the best effort class. A method is proposed to determine the scheduling resource capacity of active users in LTE networks with an admission control to limit the number of users according to available resources. In addition to closely matched theoretical and simulated active users that can be accommodated in the system, promising results are provided for system delay, throughput, and user mobility.